The cathedral of Cefalů, consecrated to the Savior and to Sts Peter and Paul, was built by Roger II, king of Sicily. The cornerstone was laid on June 7, 1131, a few months after Roger II was crowned. When Roger II died in 1154, the cathedral was still far from finished. The final consecration is documented as having taken place in 1267.

The cathedral's chief decorations are the mosaics in the choir, which cover only the apse and bay just in front of it. Mosaics were here first employed for the decoration of a church interior in Sicily; Byzantine mosaic artists were entrusted with their creation. However, by the time the mosaics on the side walls of the choir were undertaken, native artists were working alongside the imported ones. Unlike the medieval mosaics in Rome, where there was a deliberate return to Early Christian motifs originated in Rome, the pictorial program is wholly Byzantine in flavour.

The bust of the Pantocrator was given the most prominent spot available, namely the apse calotte. Beneath the apse calotte with its dominant Pantocrator figure, the mosaic is divided into three registers, Mary occupying the centre of the top one, where she is pictured as an intercessor. In the two lower registers the apostles are pictured on a somewhat smaller scale.

The pictorial program in the bay in front of the apse consists of single figures, with no scenic depictions. The side walls present figures from the Old Testament, sainted deacons and warriors and Latin and Greek teachers of the church. Angels of various orders are distributed across the caps of the cross-ribbed vault.